Significant Changes Due To Topic 606 (Summary of the Effects of Adoption of ASC Topic 606 on the Company's unaudited Consolidated Statement of Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income (loss)	$ 2,008	$ 313	$ 2,775	$ (342)
Accounting Standards Update 2014-09 [Member]
Net income (loss)		313		(342)
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Net income (loss)		58		216
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Net income (loss)		$ 255		$ (558)